PI3Kα, consisting of the p110α isoform of the catalytic subunit of PI 3-kinase (encoded by PIK3CA) and the p85α regulatory subunit (encoded by PI3KR1) is activated by growth factor receptors. The identification of common oncogenic mutations in PIK3CA has driven the development of many inhibitors that bind to the ATP-binding site in the p110α subunit. Upon activation, PI3Kα undergoes conformational changes that promote its membrane interaction and catalytic activity, yet the effects of ATP-site directed inhibitors on the PI3Kα membrane interaction are unknown.
View Article and Find Full Text PDFMen taking antioxidant vitamin E supplements have increased prostate cancer (PC) risk. However, whether pro-oxidants protect from PC remained unclear. In this work, we show that a pro-oxidant vitamin K precursor [menadione sodium bisulfite (MSB)] suppresses PC progression in mice, killing cells through an oxidative cell death: MSB antagonizes the essential class III phosphatidylinositol (PI) 3-kinase VPS34-the regulator of endosome identity and sorting-through oxidation of key cysteines, pointing to a redox checkpoint in sorting.
View Article and Find Full Text PDFPIK3CA, which encodes the p110α catalytic subunit of PI 3-kinase alpha (PI3Kα), is one of the most frequently genetically activated kinases in solid tumors. In two back-to-back papers, Varkaris and colleagues report on the development of a novel allosteric PI3Kα-mutant-selective inhibitor and early clinical experience with this compound. See related article by Varkaris et al.
View Article and Find Full Text PDFHarnessing the potential beneficial effects of kinase signalling through the generation of direct kinase activators remains an underexplored area of drug development. This also applies to the PI3K signalling pathway, which has been extensively targeted by inhibitors for conditions with PI3K overactivation, such as cancer and immune dysregulation. Here we report the discovery of UCL-TRO-1938 (referred to as 1938 hereon), a small-molecule activator of the PI3Kα isoform, a crucial effector of growth factor signalling.
View Article and Find Full Text PDFBoth subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are effective in reducing symptoms and medication scores and inducing long-term efficacy in patients with allergic rhinitis (AR). However, SLIT has been associated with poor patient adherence. This study investigates the factors impacting dropout rates from SLIT in house dust mite (HDM)-sensitized AR patients.
View Article and Find Full Text PDFRelaxin family peptide receptors (RXFPs) are the potential therapeutic targets for neurological, cardiovascular, and metabolic indications. Among them, RXFP3 and RXFP4 (formerly known as GPR100 or GPCR142) are homologous class A G protein-coupled receptors with short N-terminal domain. Ligands of RXFP3 or RXFP4 are only limited to endogenous peptides and their analogues, and no natural product or synthetic agonists have been reported to date except for a scaffold of indole-containing derivatives as dual agonists of RXFP3 and RXFP4.
View Article and Find Full Text PDFPhosphoinositide 3-kinase β (PI3Kβ) is regulated by receptor tyrosine kinases (RTKs), G protein-coupled receptors (GPCRs), and small GTPases such as Rac1 and Rab5. Our lab previously identified two residues (Gln and Ile) in the helical domain of the catalytic subunit (p110β) of PI3Kβ whose mutation disrupts binding to Rab5. To better define the Rab5-p110β interface, we performed alanine-scanning mutagenesis and analyzed Rab5 binding with an pulldown assay with GST-Rab5 Of the 35 p110β helical domain mutants assayed, 11 disrupted binding to Rab5 without affecting Rac1 binding, basal lipid kinase activity, or Gβγ-stimulated kinase activity.
View Article and Find Full Text PDFThe serum and glucocorticoid-regulated kinase (SGK) family has been implicated in the regulation of many cellular processes downstream of the PI3K pathway. It plays a crucial role in PI3K-mediated tumorigenesis, making it a potential therapeutic target for cancer. SGK family consists of three isoforms (SGK1, SGK2, and SGK3), which have high sequence homology in the kinase domain and similar substrate specificity with the AKT family.
View Article and Find Full Text PDFThe phosphatidylinositol 3-kinase (PI3K) pathway is involved in many cellular functions including cell growth, metabolism, and transformation. Hyperactivation of this pathway contributes to tumorigenesis, therefore, PI3K is a major target for anticancer drug discovery. Since the PI3Kα isoform is implicated mostly in cancer, we conducted a high-throughput screening (HTS) campaign using a 3-step PI3K homogenous time-resolved fluorescence assay against this isoform bearing the H1047R mutation.
View Article and Find Full Text PDFNovel series of limonin derivatives (V-A-1-V-A-8, V-B-1-V-B-8) were synthesized by adding various tertiary amines onto the C (7)-position of limonin. The synthesized compounds possessed favorable physicochemical property, and the intrinsic solubility of the novel compounds were significantly improved, compared with limonin. Different pharmacological models were used to evaluate the analgesic and anti-inflammatory activities of the target compounds.
View Article and Find Full Text PDFThrombin has long been suggested as a desirable antithrombotic target, but anti-thrombin therapy without anti-platelet thereby has never achieved the ideal effect. HY023016 is a novel compound, in our previous study, it exerted better anti-thrombotic than dabigatran etexilate. The present study aims to illustrate the excess anti-thrombotic molecular mechanisms of HY023016 through thrombin anion exosites and the platelet membrane receptor subunit glycoprotein Ibα (GPIbα).
View Article and Find Full Text PDFJ Huazhong Univ Sci Technolog Med Sci
June 2017
Nasal polyp (NP) is a common chronic inflammatory disease of the nasal cavity and sinuses. Although some authors have suggested that NP is related to inflammatory factors such as interleukin (IL)-1β, IL-5, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-α, and IL-17, the mechanisms underlying the pathogenesis and progression of NP remain obscure. This study investigated the expression and distribution of IL-17 and syndecan-1 in NP, and explored the roles of these two molecules in the pathogenesis of eosinophilic chronic rhinosinusitis with nasal polyps (Eos CRSwNP) and non-Eos CRSwNP.
View Article and Find Full Text PDFPhosphoinositide 3-kinases (PI3Ks) are major regulators of many cellular functions, and hyperactivation of PI3K cell signalling pathways is a major target for anticancer drug discovery. PI3Kα is the isoform most implicated in cancer, and our aim is to selectively inhibit this isoform, which may be more beneficial than concurrent inhibition of all Class I PI3Ks. We have used structure-guided design to merge high-selectivity and high-affinity characteristics found in existing compounds.
View Article and Find Full Text PDFThe generation of thrombus is not considered as an isolated progression without other pathologic processes, which may also enhance procoagulant state. The purpose of this study was to assess whether HY023016, a novel dabigatran prodrug and an oral direct thrombin inhibitor, or dabigatran etexilate, another thrombin inhibitor can improve the state of whole blood hypercoagulability in vitro/vivo. By using whole blood flow cytometry we explored the effects of HY023016 and dabigatran etexilate on thrombin and ADP-induced human platelet-leukocyte aggregation generated in vitro.
View Article and Find Full Text PDFThe NLR pyrin domain containing 3 (NLRP3) inflammasome plays a crucial role in lung disease and may have a similar role in upper respiratory tract inflammation. We therefore constructed a C57BL/6 mouse model of acute rhinosinusitis induced by Staphylococcus aureus and investigated the role of the NLRP3 inflammasome in this model. Mice were classified as non-inoculated group (group A) and inoculated groups (groups B, C, D and E, sacrificed 1, 3, 7 and 14 days after inoculation, respectively).
View Article and Find Full Text PDFJ Huazhong Univ Sci Technolog Med Sci
August 2014
Recent studies indicated that interleukin (IL)-17, growth-related oncogene (GRO)-α and IL-8 play an important role in the pathogenesis of nasal polyps. However, the effects of the increased amount of IL-17 and the production of GRO-α and IL-8 in human nasal polyp fibroblasts are not completely understood. This study aimed to determine the effects of the increased IL-17 on the changes of GRO-α and IL-8 expression in human nasal polyp fibroblasts and further investigate the mechanism of neutrophil infiltration in nasal polyps.
View Article and Find Full Text PDFThe aim of this study was to evaluate the therapeutic efficacy and the safety of transarterial infusion (TAI) with gemcitabine and oxaliplatin in patients with unresectable pancreatic cancer (PC). After celiac arteriogram and super-mesenteric arteriography, 1000 mg/m gemcitabine and 100 mg/m oxaliplatin were infused through 4- or 5-Fr catheters in arteries supplying blood to the tumor. In cases in which the blood-supplying artery could be selectively catheterized, the infusion was performed through a 3-Fr catheter placed in the tumor-supplying artery.
View Article and Find Full Text PDFHepatobiliary Pancreat Dis Int
October 2013
Background: Liver biopsy is the "gold standard" for evaluating liver disorders, but controversies over the potential risk of complications and patient discomfort still exist. Using a 21G fine needle, we developed a new biopsy procedure, fine needle aspirating and cutting (FNAC). Our procedure obtains enough tissue for pathological examination and meanwhile, reduces the risk of biopsy complications.
View Article and Find Full Text PDFIntroduction: Thrombin is a multifunctional trypsin-like serine protease that plays key roles in coagulation and thrombogenesis. HY023016, a novel Dabigatran prodrug, is an oral direct thrombin inhibitor. The purpose of this study was to compare the anti-thrombotic activities and haemorrhagic effects of HY023016 with Dabigatran etexilate and tetramethylpyrazine in several animal thrombosis models.
View Article and Find Full Text PDFA novel series of prodrugs containing dabigatran and methyl (E)-3-(4-hydroxy-2-methoxyphenyl)propenoate (methyl ferulate) were synthesized. All of them reveal the effect of thrombin-induced anti-platelet aggregation in vitro. In addition, in vivo experiment shows that one of the target compounds, X-2 (ED50=3.
View Article and Find Full Text PDFBackground: Stent occlusion by tumor ingrowth or overgrowth is the main cause of jaundice recurrence after metal stent insertion in patients with malignant obstructive jaundice (MOJ). The application of intraluminal brachytherapy (ILBT) in patients with MOJ results in local control of malignant tumors, which prolong stent patency.
Purpose: To evaluate the safety of ILBT in pig bile ducts using ribbons of iodine-125 ((125)I) seeds.